Diagnosis: A moderately-sloped head and bicuspid teeth in the outer row of the jaws place this species in Maylandia (Ref. 86409). A black pelvic fin, a dark-blue cheek and preorbital area, and a blue dorsal fin without a black submarginal band in breeding males and the light-brown coloured females that have yellow fin-margins distinguish M. sciasma from all other members of Maylandia (Ref. 86409). Breeding males of M. sciasma are distinguished from those of some populations of M. zebra by the presence of a single interorbital bar, vs. 2 in M. zebra, and by black pigment on the anterior membranes of the anal fin; female M. sciasma cannot reliably be distinguished from those of most other members of the Aurora group, but differ from those of M. aurora by more vertical bars below the dorsal fin, 7–10 vs. 6 (Ref. 86409).

Description: Dorsal snout profile slightly concave to straight; mouth cleft with slightly downward angle; jaws isognathous; teeth on dentary in two to three rows, on premaxilla in two to four rows; outer row teeth typically bicuspid anteriorly and unicuspid posteriorly, inner rows tricuspid, innermost row unicuspid; lower pharyngeal jaw with numerous slender teeth with teeth in posterior row slightly larger; portion of upper dental arcade normally visible in closed mouth; tips of teeth in premaxilla and dentary in V-shaped line with anteriormost in upper and lower jaw furthest apart and separate in closed mouth (Ref. 86409). Lateral scales ctenoid (Ref. 86409).

Colouration: Lateral body colouration of breeding males blue dorsally with 7-10 gray bars, white ventrally, and blue/gray caudal peduncle; preorbital, cheek, and operculum dark blue/gray; blue opercular spot; gray/blue gular region; premaxillary and maxillary blue/gray; blue/gray interorbital bar; dorsal fin blue with light-blue lappets; caudal fin with gray rays and blue membranes; anal fin blue/gray with 2-7 yellow ocelli; pelvic fin black with white leading edge; pectoral fin clear (Ref. 86409). Females brown dorsally and gray/white ventrally; head brown with blue highlights on operculum and gray/green opercular spot; white gular region; dorsal and anal fins yellow/brown; proximal third of caudal fin dark brown, distal third light brown/yellow, membranes with faint blue spots; pelvic fin with white leading edge, first 2 rays and membranes yellow/brown with remaining clear; pectoral fin clear (Ref. 86409).